(1) Field of the Invention
This invention relates generally to containers used to dispense and store flowing materials such as a liquid or powder and relates particularly to those containers molded of a plastic material which include a pouring aperture cooperating with a pivotally secured tab whereby liquid may be dispensed through the pouring aperture by pivoting the tab away from its sealing position and resealed by pivoting the tab to a closed position.
(2) Prior Art
With the advent of disposable plastic containers for selling and distributing liquid products such as shampoos, soaps, cosmetics and the like, practitioners in the container design arts have employed a number of systems in an attempt to provide an easily utilized container having an attractive appearance. Typically, the liquid products are sold in a molded plastic bottle which terminates on its upper end in a cylindrical neck. A molded plastic cap is usually employed to seal the bottle which includes means for attachment to the container neck in a sealing manner. In such containers the cap is removed to dispense the liquid and the container is thereafter resealed by returning the cap to the neck. In the earliest cap and container configurations, the neck supported a plurality of threads and defined a relatively large discharge aperture. Correspondingly, the cap comprised a simple closed end cylindrical member having an integral top surface and an interior thread compatible with the thread on the container neck. Container access was achieved by simply unthreading the cap from the neck and pouring the liquid from the container to the neck. Conversely the container was resealed by simply threading the cap back upon the neck until the upper portion of the container neck engaged a receiving surface on the cap interior affecting a seal.
As practitioners in the art became more and more adept at container design and production, there evolved various variations and improvements directed toward increasing the consumer appeal of the product by improving the ease of container uses. For example, one structure provides a simple slide member valve supported on the cap which is moveable between a first position affecting sealing and slidably moveable to a second position in which a pouring aperture is unabstructed. This system is most commonly utilized in dispensers of soap, shampoos and the like. Another frequently used container system employs a cap which comprises a molded plastic cap having a generally flat top surface and a generally cylindrical side depending therefrom to form a closed internal cavity. In most cases, the interior sides of the cap are threaded to cooperate with the external neck threads on a container to secure the cap to the container neck, in a manner similar to the prior devices described above. The improvement provides a cap which can be opened and closed without removal from the neck. A pivotally mounted tab member is secured to the top portion of the cap and may be pivoted to a first position in which the tab member is seated within a receiving channel formed in the top of the cap. The receiving channel is generally configured to receive the entire tab member in the closed position thereby providing a generally flush top surface on the cap. The tab member may also be pivoted to a second position in which the tab assumes a obtuse angle with the top surface of the cap. The cap channel, which receives the tab, further defines a small pouring aperture while the mating surface of the pivotable tab defines a downwardly extending plug member configured to fit within and form a seal of the small aperture when the tab is placed in the flush position.
The use of such tab type caps for containers storing soaps, shampoos and the like have provided a considerable improvement in the ease of use and consumer appeal over prior devices requiring cap removal and have enjoyed substantial consumer acceptance and appreciation. However, particularly when used with soaps, shampoos and other liquids which tend to have very high lubricating properties, a problem has arisen in that the repeated use of the tabbed cap causes the liquid to collect around the supporting hinge of the tab. Since the supporting hinge is the sole means of attachment between the tab and the cap, the lubrication of the hinge attachment resulting, frequently causes the tab to become unintentionally separated from the cap. This separation often occurs while the tab is being moved between its two operable positions and is annoying to consumers.
There remains therefore a need in the art for an improved tab style cap structure which better resists the tendency to loosen and disengage in use with liquids having a high lubrication property.